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    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
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    <title>Document</title>
    <style>
        div:target{
            color: green;
            font-size: 50px;
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<body>
    <div id="box">国文</div>
    <a href="#box">点击让国文变绿</a>
</body>
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